1. Field of the Invention
This invention relates to new and useful improvements for liquid pumps and more particularly, to high pressure pumps for delivering a stream of water or other liquid at high velocity for jet washing or cleaning of surfaces.
2. Brief Description of the Prior Art
Sergeant U.S. Pat. No. 745,298 discloses a compressor having a series of pistons of varying diameter for compressing gasses.
Hoerbiger U.S. Pat. No. 1,759,617 discloses a gas compressor with a pair of line cylinders of different diameter and a larger and smaller piston for compression.
Wineman U.S. Pat. No. 2,365,234 discloses a pump having two different cylinders of varying diameter in line and a single piston fitting both the larger and smaller cylinders for delivering liquid and gasses to a common system.
Green U.S. Pat. No. 3,155,041 discloses a pressure apparatus comprising a pump having two or more cylinders of varying diameter and pistons fitting said cylinders and operated by a single pump rod.
There has been a need for a satisfactory high-pressure pump for delivering water or other liquid at very high velocity for jet washing or cleaning of various surfaces.